Methods for elimination of oil slicks

ABSTRACT

1. THE METHOD OF REMOVING OILS AND HYDROCARBONS FROM THE SURFACE OF A BODY OF WATER COMPRISING DISPERSING A FREEZE-DRIED HYDROCARBON CONSUMING MICROOGANISM COMPOSITION COMPRISING MICROORGANISMS ADSORBED WITHIN AN INORGANIC MICROPOROUS CARRIER ONTO SAID OILS AND HYDROCARBONS, SAID SURFACE HAVING WATER AND MOISTURE PRESENT WHEREBY SAID MICROORGANISM COMPOSITION IS ACTIVATES, ADN ALLOWING SAID MICROORGANISM COMPOSITION TO REMAIN IN CONTACT WITH SAID OILS AND HYDROCARBONS WHEREBY THE MICROORGANISMS IN SAID COMPOSITION DIGEST AND REMOVE THE OILS AND HYDROCARBONS.

United States Patent "ice 3,843,517 METHODS FOR ELIMINATION OF OILSLICKS Robert W. McKinney, Adelphi, Md., Andrew L. Dixon,

Jr., Wickliife, Ohio, and Raymond L. Jordan, Baltimore, Md., assignorsto W. R. Grace & Co., New York,

No Drawing. Continuation-impart of abandoned application Ser. No. 1,512,Jan. 8, 1970. This application Dec. 17, 1970, Ser. No. 99,253

Int. C1. C02!) 9/02 U.S. Cl. 21011 Claims ABSTRACT OF THE DISCLOSURE Ina preferred mode, cultures containing hydrocarbon and oil consumingmicroorganisms with or without nutrients are adsorbed in a carrier suchas clays, vermiculites, silica gels, perlites and similar materials andfreeze-dried to form useful compositions. These compositions are placedon oil films or layers which are on fresh or salt water, or on beachesor river banks, or in storage tanks, ships tanks and so on. The carrieradsorbs and concentrates the oil in the presence of the microorganismsand the microorganisms consume the oil. The microorganisms remain viablein these compositions even after long storage periods. In an alternativecomposition, the microorganisms may be freeze-dried and then admixedwith a carrier such as clays, vermiculites, perlites, silica gels or soon.

Cross-Reference To Related Application This application is acontinuationdn-part of our a plication U.S. Ser. No. 1,512, filed Jan.8, 1970, now abandoned.

Background of the Invention This invention relates to oil andhydrocarbon consuming compositions useful for eliminating oilcontamination from shorelines and fresh and saline waters. Thisinvention further relates to methods for producing these oil andhydrocarbon consuming compositions as well as methods for their use.This water on which the deleterious oil and hydrocarbons are present maybe that of streams, rivers, lakes, bays, oceans or contained water suchas bilge water, tank water, tanker ballast water and so on. Inparticular, it relates to freeze-dried microorganism compositions andthe use of these compositions to consume and remove oils andhydrocarbons.

The conventional methods that are presently used for removing oil fromwater involve spreading adsorbent materials such as straw, clay, silicaor kieselguhr particles, filaments, etc., onto the oil slicks. Thesematerials may optionally be coated with an oleophilic agent. Whenplacedv on the oil, these materials absorb the oil. Some materials, suchas straw, continued to float after absorbing oil. These materials areremoved from the water surface by hand. Other materials sink afterabsorbing oil due to the increased specific gravity. Techniques forelimination of oil by sinking it leave masses of oil and hydrocarbons onthe bottom of bodies of water. Furthermore, it has been shown that afterseveral months under water, the sunken mass is still mobile and oilcould be released from it by agitation. The sunken oil could also foulfishing gear and sinking cannot be done in the vicinity of beds ofoxyters or other shellfish. The compositions and methods of thisinvention solve this problem of oil removal by having microorganismsdigest the oil to harmless waste products, thereby removing the oil. Inthe present invention, freeze-dried microorganisms, mixtures of thesemicroorganisms and composites of these microorganisms are convenientlystored and spread on oil slicks to digest these slicks when such anemergency arises. The oil slick is then rapidly 3,843,517 Patented Oct.22, 1974 digested to essentially carbon dioxide and water, effectivelydissipating the pollution.

In the prior art, microorganisms have been used to convert oil toprotein. For example, U.S. Pat. No. 2,769,750 discloses admixingparticulate anhydrous inert adsorbents with hydrocarbons and/0roxygenated hydrocarbons. This homogeneous mixture is further mixed witha nutrient inoculated with hydrocarbon-consuming microorganisms. Theadsorbents are normally added in suflicient amounts so that theadsorbent hydrocarbon mixture is a dry powder. The adsorbents arepreferably naturally occurring clays, such as kaolinic clay. Furtherbacterial cultures have been freeze-dried, one technique being disclosedin U.S. Pat. No. 3,261,761. That process involves growing a culture inthe presence of a metal salt such as NaCl; diluting the culture withbuffer and sugar solutions; pre-cooling it to 0 C. to 1 C., reducing itstemperature to 5 C. or lower by applying a vacuum and subliming off themoisture by maintaining it at 5 C. or below. Concerning other techniquesof drying microorganisms, U.S. Pat. No. 2,919,194 discloses suspendingfine particles of Wet yeast in a liquid and drying the suspended yeastby evaporating the water. The Water evaporation is done by contact witha stream of inert gas. This patent teaches this type of drying aspreferred when yeast cells are being procesed. U.S. Pat. No. 3,224,946relates to the use of synthetic or natural zeolites in microbialconversion of hydrocarbons to other products. The hydrocarbons areabsorbed on the molecular sieves or within their crystalline porestructure. The hydrocarbon containing zeolites are contacted with thewater containing the necessary nutrients and hydrophilic microbes areadded. This allows the microbes to retain contact with its nutrientsource and yet attack the hydrocarbons. It can readily be appreciatedthat there would be extreme difficulties in using this system toeliminate oil slicks on large, open bodies of Water, if it could be usedin that manner at all. To further illustrate the unpredictability ofsuch a use, the patent discloses that asbestos and bentonite failed toperform as the zeolite.

It is an object of this invention to dissipate oil and similarhydrocarbon pollution by digesting these oils and hydrocarbons withmicroorganisms.

It is further an object of this invention to set out microorganismcompositions which can be stored for long periods of time, but whichwhen spread on an oil or simi lar hydrocarbon surface are rapidlyactivated and effectively remove this surface.

It is also an object of this invention to set out freezedriedmicroorganism compositions which are storable for long periods of time,are easily dispersed on an oil or by drocarbon surface, and which arereadily activated.

It is additionally an object of this invention to set out methods forremoving oil and similar hydrocarbon slicks from rivers, lakes, streams,bays, oceans, shorelines, land areas, or from contained waters such asthat in tanks and so on.

And further, it is an object of this invention to set out a unique useof the compositions of this invention in crude oil tanker operations,whereby not only is pollution from this source abated, but operationalsafety is increased.

Brief Description of the Invention This invention comprises compositionsand methods for removing oils and other hydrocarbons from surfaces suchas shorelines and those of fresh and salt Water, whether contained oressentially open. The fresh and salt water surfaces may be those ofnatural or man-made bodies of water or water contained in tanks or othercontainers. The compositions preferably comprise freeze-drying, (i)microorganisms along with nutrients, or (ii) microorganisms within acarrier material, or (iii) microorganisms within a carrier alsocontaining nutrients. Alternatively, freeze-dried microorganisms may beadmixed with a carrier material which may or may not contain nutrients.For removal of a hydrocarbon or oil, any of these compositions, or amixture, is placed on the hydrocarbon or oil deposit to be removed. Theoil or hydrocarbon is then digested by the microorganisms.

Detailed Description of the Invention The process of this invention forpreparing freeze-dried cultures of hydrocarbon consuming microorganismsinvolves preparing a culture, which is an aqueous medium suitable forgrowing and sustaining hydrocarbon-consuming microorganisms. Thisculture, or a culture mixture, is then preferably either free-dried, oradsorbed on and in a carrier, optionally along with nutrients, andfreezedried. In use, the composition is dispersed onto the oil orhydrocarbon surface with the microorganisms digesting and removing thisoil and hydrocarbon.

The hydrocarbon consuming or converting microorganisms useful in thisinvention include hydrocarbon consuming or converting bacteria, molds,yeast, fungi and actinomyces. The terms oil consuming" and hydrocarbonconsuming are used interchangeably and are meant to encompass all of thecompounds and compositions encompassed within the terms commonly knownas oil, crude oil, gas oil, hydrocarbons, and petroleum. Examples ofspecific useful species of microorganisms are: Pseudomonas aeruginosa,Pscudomonas boreopolis, Pseudomonas fluorescens, Pseudomonas .s'yringal,Pseudomonas natriegens, Pseudomonas oleovorans, Methanomonas methanica,Desulfovibrio desulfuricans, Micrococus parafi'z'nae, Achromobacteragile, Achromobacter centropunctatum, Bacterium aliphaticum, Bacteriumbe azoli, Bacterium hidium, Bacterium naphtha linicus, Bacillumamylobacter, Bacillus megaterium, Bacillus subtilis, Bacillushexacarbovorum, Bacillus tolulicum, Mycabacterium album, Mycobacteriumrubrum; Mycobacterium lacticola, Nocardia opacus, Nocardia corallina,Nocardia farcinica, Actinomyces oligocarbophilus, Candida pulchenine,Candida utiliz, Candida tropicolis, Candida lipolytica. Various speciesof Debaryomyces, Endomyces, Hansenia, Monillia, Oidila and Torulopis arealso useful, as also are mixtures of various microorganisms. The solerestriction on the type of microorganism is that only nonpathogenicmicroorganisms should be used.

A single microorganism species does not have the ability to continue allthe various types of chemical compounds present in oil or any complexhydrocarbon mixture conraining, for example, aliphatic, cyclic, aromaticand olefin compounds or compounds of a wide range of molecular weight ormixtures of various types of compounds of widely ranging molecularweights. Therefore, a mixture of microorganisms is selected which willcontain species capable of consuming all the major components of the oilor hydrocarbon samples. Either known data or preferably, separateselective analyses are used to develop the combinations ofmicroorganisms which have the ability to consume the major components ofthe oils and hydrocarbons.

The preferred carrier materials when used include clays such as kaolin,zeolites and other microporous silicaalumina materials, silica gels,vermiculites and perlites, and particularly these in hydrophilic forms.The operable materials, however, include microporous materials of theclass into which microorganisms and nutrients or microorganisms alonecan be absorbed and freeze-dried, and which will subsequently adsorb oilso as to bring this oil into a close relationship with themicroorganisms for digestion. A particularly preferred material isvermiculite and ideally an unexfoliated vermiculite. Vermiculite as usedherein refers to the group of rock-forming mineral species characterizedby a layer of latticized structure in which the silicate-layer unitshave a thickness of approximately A. (Angstrom units). The main elementspresent in the layer are magnesium, aluminum, silica, iron and oxygenwith the latter being separated by one or two sheets of water moleculesassociated with cations, such as magnesium, calcium, sodium andhydrogen. The layers have considerably lateral extent relative to thethickness of the basic IO-Angstrom-unit layer. Further, vermiculitebelongs to the phyllosilicatc group, which are characterized by thepresence of Si-O sheets formed by the linkage of three corners of eachSiOJ, tetrahedron to neighbors so that each tetrahedron has three sharedand one free oxygen. The type formula is Am(B X Vermiculite hasmonoclinic hexagonal plates and a hardness of one. The term vermiculiteas used herein therefore includes minerals consisting wholly or largelyof vermiculite, or minerals of a mixed-layer type containing vermiculitelayers as an important constituent, such as hydrobiotites andchlorite-vermiculites. Unexfoliated vermiculite is an unexpandedvermiculite. For very elfective use, the pore diameters of themicroporous carriers should be in the range of 10 A. or greater,although smaller pore sizes in the range of 5 A. can be used. In regardto particle size, this is not a critical factor, with sizes of fromwithin the micron range up to a centimeter being useful. The particlesize Will be dependent to a degree on the particular microporous carrierbeing used, that is, for example, it will be different for an exfoliatedand an unexfoliated vermiculite.

The terms oil, petroleum and hydrocarbons encompass generically all ofthe hydrocarbons and oxygenated hydrocarbons, singly and incombinations, and particularly those found in naturally occurringsubstances known as crude oils, gas oils and petroleums. Therefore, theterms cover complex mixtures of paraffin, olefiinic, acetylenic,carbocyclic and aromatic hydrocarbons. These terms further cover thisgeneric class of substances regardless of the geographic origin orsource of the substances. For simplicity, the terms oil andhydrocarbons, equivalents for purposes of this disclosure, will be usedtogether and interchangeably to denote the above generic class ofsubstances.

The term nutrients as used herein comprises those inorganic substanceswhich the microorganisms require for growth and activity. These samenutrients are generally present in the microorganism culturingsolutions. Table 1 sets out a list of common nutrients and severalsolutions of these substances. Those set out are exemplary of usefulnutrient solutions, but are by no means exclusive. Other solutions ofthese substances, as well as solutions containing other substances, canbe used to form the nutrient media.

TABLE I Bacteria nutrients, g.

Yeast Solu- Solu- Solunutrient Bacterial nutrients tion 1 tnon 2 tion 3solution, g.

Manganese sulfate Sodium carbonate- Potassium chloride. Ammoniumphosphate Distilled water The compositions for practical use inconsuming (digesting) oils and hydrocarbons require that themicroorganisms be in a suitable form for storage, handling and use. Thegeneral method for producing these microorganisms is to culture them inan aqueous nutrient media. However, it is not feasible to store, handleor use them as an aqueous media. In solving this problem, afreeze-drying is used to put the microorganisms in a suitable form.Therefore, considered as parts of the concept of this invention, (i),the microorganisms may be freeze-dried alone, (ii) freezedried alongwith nutrients, (iii) freeze-dried alone and then admixed with a carrierwhich may contain nutrients, (iv) adsorbed into a carrier andfreeze-dried, (v) or adsorbed into a carrier along with nutrients andthen freezedried. The actual stepwise techniques of freeze-drying areknown in the art and are not a separate part of this invention. Inessence, freeze-drying as known in the art and used herein comprisesconcentrating a solution of the ma terial to be dried as far aspossible, decreasing its temperature to form 1 C. to 5 C. below itssolidification point, drawing a vacuum and evaporating the solventdirectly from the solid to gaseous phase as by sublimation. During thissublimation, the temperature drops about 5 C. to 50 C. Terms other thanfreeze-drying used many times to describe this process arelyophilization or vacuum sublimation. Any commercially availablefreeze-drying apparatus may be used such as equipment manufactured bythe Vertis Company, Inc., Vacudyne Corporation, Thermovac IndustriesCorporation or the Hull Corporation. After the material has beenthoroughly dried, the temperature may be increased up into the range ofroom temperature or above, but preferably the previously freeze-driedmaterial is maintained within a desiccant atmosphere. The temperatureshould not, however, be raised up to a point where the microorganismswould be destroyed.

Optionally, in the process of freeze-drying an organic colloid may beadded to the microorganism culture prior to the lowering of thetemperature to minus 1 C. to minus 5 C. Organic colloids apparentlyprotect such cultures during freeze-drying. Although any of the commonlyused organic colloids may be used, whole skim milk is excellent for thispurpose due to its ready availability, convenience, and excellentresults.

A very suitable technique for storage is to place the microorganismcompositions into containers containing a desiccant such as silica geland vacuum seal these containers. These freeze-dried materials may thenbe stored for at least about 12 months, and where desiccated conditionsare well maintained, for considerably longer periods of time.

When the microorganism above is freeze-dried, the microorganism isseparated from the culture .solution, optionally washed, andfreeze-dried from an aqueous mixture, preferably a mixture which ismaintained at a pH of from about 5-8. In the instance offreeze-dryingalong with nutrients, the microorganism is freeze-driedessentially along with a solution as set out in Table I which containsthe necessary growth nutrient. The pH of this solution should preferablybe maintained at from about 5 to 8. These nutrients may be added to theculturing solution prior to freeze-drying, or as a still furtherembodiment the microorganism may be removed from the culturing solution,optionally washed, mixed into a nutrient solution, and freeze-dried.When the microorganism is freeze-dried already adsorbed into a carrier,the process comprises admixing the carrier with a microorganismsolution, allowing a period of from about 0.1 to 1 hour for adsorption,and after adjusting the pH to the preferred range of 5 to 8,freeze-drying. In the instance of freezedrying a composition of thecarrier microorganism and nutrients, the adsorption of the microorganismand nutrients may be carried out simultaneously or in any order,followed by the freeze-drying of the composite. Also in this instance,it is preferred to freeze-dry from a solution of about 5 to 8 pH. Theuseful buffer solutions of pH 5 to 8 are aqueous mixtures of potassiumdihydrogen phosphate or potassium monohydrogen phosphate or mixtures ofthese compounds. Some useful buffer solutions are set out in Table II.

The use of these microorganism compositions for dissipating oils andother hydrocarbons consists essentially of dispersing the freeze-driedmicroorganism composition on the hydrocarbon or oil surface. The actualtechnique used for dispersing on the hydrocarbon or oil surface is notcritical and any method which will essentially uniformly spread a layeron the surface can be used. This may be by dispersing as a dry powder oras an aqueous mixture; and can be accomplished by pneumatic spraying asa gas-solid mixture or hydraulic spraying as a liquid-solid mixture, orby the use of explosive dispersing charges similar to those used inemergency dye markers, and so on. Once on the surface of the oil, themicroorganism composition, if applied in dry form, is activated by thereadily available surrounding moisture and digestion of the oils andother hydrocarbons commences. The compositions which consist of themicroorganisms and nutrients within a carrier are especially preferred,and have yielded the faster rates of digestion and dissipation of theoils and hydrocarbons.

The specific uses of these compositions are manyfold. They can be usedon any polluting or otherwise unwanted hydrocarbon or oil surface, andthis hydrocarbon or oil may be of any layer thickness. However, theseare particularly useful for removing oil along the shorelines and inharbors where present manual techniques are very inefiective. Usingpresent techniques such as straw adsorption, it is difiicult to gatherup the oil around pier pilings, in swamps or treed areas, or in otherheavy undergrowth areas. But using the present invention, themicroorganisms may be dispersed from boats, aircraft, or from manuallycarried containers for complete digestion and dissipation of the oil.Once dispersed on the oil, the microorganisms essentially immediatelystart to dissipate the oil, evolving carbon dioxide and water asprincipal waste products, and utilizing the oil and hydrocarbon as theprotein carbon source for the formation and growth of moremicroorganisms. This microorganism growth allows for growth across theoil and hydrocarbon layer so that activity is not restricted solely tothe area of the microporous carrier loaded particles.

Another important use of these compositions is in removing oil residuesand sludges from tanks. These can be land anchored storage tanks priorto cleaning or repairing, or the tanks of tanker ships which transportcrude oils. The particular advantage in tanker operation comes as aresult of the procedure of taking in water for ballast for a return tripto an oil field area to reload with crude oil. The present technique isto dump this residual oil laden ballast water outside a harbor prior todocking for refilling with crude oil. This residual oil then pollutesthe water. Also, in this procedure of pumping out the ballast water,there is a stage when with in-rushing air there is an explosive vaporousmixture in the tanks. These problems can be obviated by the use of thecompositions of this invention. If after filling the tanks with ballastwater to the desired level, any of the microorganism compositions ofthis invention, or mixtures, are added, the oil will be consumedproducing carbon dioxide which is useful in inhibiting the formation ofan explosive atmosphere during the procedure of pumping out of theballast water. Further, there will be essentially no water pollution.

The following examples will aid in explaining, but should not be deemedas limiting, the instant invention. In all cases, unless otherwisenoted, all parts and percentages are by weight.

EXAMPLE 1 A sample of pond water from the research laboratory site of W.R. Grace & Co., at Clarksville, Md., was covered with a layer ofn-tetradecane. Over a period of days a thin intermediate layer formedbetween the water and hydrocarbon layers. The surviving organisms in theintermediate layer were cultured in nutrient agar media at 37 C. for aweek. This nutrient agar solution comprises A portion of themicroorganisms from Example 1 are TABLE III Growth On MicroorganismMicroporous carrier oil H ydrophillie vermiculite .gery good. oo

freeze-dried and admixed with vermiculite particles (Zon- 5-Hydrophillic silica gel -Very good elite passed through a US. Seriessieve size No. 40 and b which has a bulk density of 45 lbs./ft. Eachtype of Cangiiriatropimlglr--- -Vermiculite Do. microorganism obtainedfrom Example 1 is freeze-dried Hydmpmlhcvermimh E3: and admixed withhydrophylic vermiculite. Candida lipo- 1O aci u mu q t lytica andPseudomonas fluorescens cultures (purchased from American Type CultureCollection, 12301 Park Lawn Drive, Rockville, Md.) are freeze-dried andad- EXAMPLE 4 mixed with the vermiculite particles. Each culture is Theseries of microorganisms of Table IH were freezefreeze-dried by placingabout 5 ml. of the culture and dried from an admixture which alsoincluded skim milk 0.5 ml. of sterile skim milk in a Virtis FreezeDrying in a concentration of 4 percent by weight of the micro- Cabinet,Model 2078, reducing the temperature to beorganism concentration. Theresults were essentially the tween 0 C. and minus 1 C., applying avacuum of about same as set out in Table III. 1p. which reduces thetemperature to about minus 50 C. The temperature is maintained in therange of minus 5 EXAMPLE 5 C. to minus 50 C. until all the moisture issublirned OK, In this example, a series of microorganisms were adwhichis about 1 to 3 hours. The pressure is then raised mixed with one of thenutrient solutions of Table I and a to atmospheric pressure and thetemperature is raised to microporous carrier, and freeze-dried. Theadmixing of room temperature. the three components allows for both thenutrients and Synthetic sea Water is then prepared and placed inmicroorganism culture solution with 10 g. of nutrient glass trays. Foursets of oil slicks are prepared by comsolution and 5 g. of microporouscarrier for from 3 to 15 bim'ng each of the following materials: WestTexas crude minutes. This mixture is then placed in a freeze-dry oil (13ml.), Esso motor oil (3 ml.), n-tetradecane (3 ml.) cabinet andfreeze-dried as in Example 4. Table IV sets and n-pentane (3 ml.). Aportion of the microorganism out the microorganisms, microporouscarrier, nutrient composition of Example 1 and the Candidalipolyticasolution and the relative microorganism grown on the oilvermiculite composition and Pseudomonas fluorescensfilm.

TABLE IV Nutrient solution of Growth on Microorganism Mieroporouscarrier Table I oil film Candida Zipolytica vermiculite Solution 1 Verygood. Candida Zipolgticu" Hydropliyllic vermiculite do Do. Candidalipolytica Silica gel Solution IL-.. Good. Pseudomoflas natrieqem doSolution I- Do. Bacillus subtilzs Hydrophyllie silica gel Solution IIDo. Micrococcus paroflinae. Hydrophyllic vermiculit Solution I. Verygood. Paeudomonas fiuorescem. do do Good. Candida utilis do SolutionIII.-- Very good. Bacterium aliphaticum Vermieulite Solution IL--- Good.Candida tropicalis Meta kaolin Solution I-.-- Do.

vermiculite composition are placed individually on each EXAMPLE 6 2 flii P 2 gi g' gg igig gzg A series of microorganisms (259) were collectedfrom 3 13 rga Isms e 1 A e p oil and hydrocarbon rich environments suchas soils EXAMPLE 3 around refineries and oil wells, and from the fueltanks of aircraft and ground vehicles. These microorganisms, after Inthis example, a series of microorganisms are adbeing isolatfid, wereScffiened gfOWth 011 Ibdecane, mixed with microporous carriers and thenfreeze-dried. Decalin and fp These three hydrocarbons were The admixingpermits the microorganisms to be adsorbed chosen as yp 0f the classfisof c"Jll'lpollllds found on and within the microporous carrier. Admixingis by in crude The five mifiroofganisms which gmW best ild agitation forfrom 3 to 15 minutes of 5 of on each hydrocarbon were selected forcombined use to miculite, kaolin clay, or silica gel. During admixing,the consume hydrocarbon and OH samples These micropH is maintainedbetween 5 and 8. This pasty mixture is Organisms are identified y genusand p y Culture then placed in the freeze-drying cabinet and thetemperanumber p y Laboratories, Ffedal'icksbufg, ture lowered to minus 1C. to minus 5 C. The pressure V in Table is then lowered to 1 1. whichdrops the temperature to TABLE V about minus 35 C. to minus 50 C.Freeze-drying is Screenin complete in 1 hour. The material is thenadjusted to Microorganism Hydrocarbon ambient conditions, but maintainedin a desiccated atmos- S 90 n-Decanephere. Table III sets out a seriesof microorganisms, and SL-463 (Achromobacter) Do. the microporouscarriers-into which they were adsorbed SL-Sll Do. on and into andfreeze-dried. The gas oil, West Texas SL525* Do. Devonian Gas Oil,500-800 F. cut, is used to determine SL-545 (Nocardia) D0. the etfectivedigestion of oil. The degree of microorgan- SL-169 (Bacillus subtilis)Decalin ism growth on the oil is determined by visual observation. sfootnotes at end of ta 9 TABLE V-Continued Screening Microorganism:Hydrocarbon SL-217 Decalin. SL-l4 (Flavobacterium) Do. SL-520(Pseudomonas fluorescens) Do. SL525* Do. SL-235 Naphthalene. SL-252(Achromobacter) Do. SL-260 (Bacillus) Do. SL-5l9 (Bacillus) Do. SL-559(Nocardia) Do.

*Good growth on both n-decane and Decalin.

A portion of each of the microorganisms of Table V were separatelyadmixed with vermiculite by mechanical stirring and freeze-dried usingthe same procedure of Example 3. Another portion of each of themicroorganisms in Table V, and a portion of Candida lipolytica, wereadmixed first with each other, and then with vermiculite (designatedG-). Admixing is by mechanical stirring. This microorganism mixturecomposite is freeze-dried using the same procedure as Example 3. TableVI sets out the growth on and dissipation of an oil mixture using themicroorganisms which have been adsorbed in and on vermiculite singly andfreeze-dried, and the microorganism mixture adsorbed in an on thevermiculite and freeze-dried.

The combined microorganism mixture gives the best results for oil filmdissipation.

EXAMPLE 7 A portion of the microorganisms designated 6-10 in Example 7are admixed together along with a silica gel carrier. Admixing is bymild stirring for minutes. This composite of microorganism cultureadsorbed into and on the silica gel is then freeze-dried using a VirtisFreeze Drying Cabinet, Model 2078. This freeze-dried composite is thenplaced on an oil slick (West Texas Devonian Gas Oil) produced on thelake at the Washington Research Center of W. R. Grace & Co. The slick,along with lake bank staining from the slick, was mostly dissipatedwithin one week, with no traces left after 2 /2 weeks.

EXAMPLE 8 The tank of an oil tanker was simulated by filling a 50 gallontank with synthetic sea water (salt water solution). On top of thisseawater an oil layer of West Texas Devonian Gas Oil was placed to adepth of A inch. A portion of the microorganism composite of Example 7was placed on the oil film. The tank was sealed except for a vent pipe.There was good microorganism growth on 10 the oil layer, and the oillayer was substantially dissipated in two weeks.

What is claimed is:

1. The method of removing oils and hydrocarbons from the surface of abody of water comprising dispersing a freeze-dried hydrocarbon consumingmicroorganism composition comprising microorganisms adsorbed within aninorganic microporous carrier onto said oils and hydrocarbons, saidsurface having water and moisture present whereby said microorganismcomposition is activated, and allowing said microorganism composition toremain in contact with said oils and hydrocarbons whereby themicroorganisms in said composition digest and remove the oils andhydrocarbons.

2. The method of Claim 1 wherein said freeze-dried microorganismcomposition consists essentially of a freezedried composite ofmicroorganisms within a microporous carrier.

3. The method of Claim 1 wherein said freeze-dried microorganismcomposition consists essentially of a freeze-dried composite ofmicrorganisms and nutrients within a microporous carrier.

4. The method of Claim 1 wherein said dispersing is by pneumaticallyspraying as a gas-solid microorganism composition mixture.

5. The method of Claim 1 wherein said dispersing is by hydraulicallyspraying as a liquid-solid microorganism composition mixture.

6. The method of Claim 1 wherein said dispersing is by an explosivecharge.

7. The method of Claim 1 wherein said oils and hydrocarbons are on anopen water surface.

8. The method of Claim 1 wherein said oils and hydrocarbons are on acontained water surface.

9. The method of Claim 8 wherein said oils and hydrocarbons on thecontained water surface are within the tanks of an oil tanker ship.

10. A method of eliminating a hydrocarbon contaminant film from thesurface of a body of water, comprising the step of distributing abacteria strain consisting essentially of a strain selected from thegroup consisting of Pseudomonas fluorescens and Pseudomonas aeruganosaon the hydrocarbon film, said bacteria being present in a concentrationsufficient to metabolize the hydrocarbon to produce non-contaminatingwater soluble products.

References Cited UNITED STATES PATENTS 3,616,204 10/1971 Linn -3 H2,742,398 4/1956 ZoBell 195-3 H 3,185,216 5/1965 Hitzman 195-3 H3,013,946 12/1961 Lurnb et al. 195-116 X 3,769,164 10/1973 Azarowicz210-11 3,105,014 9/1963 Harrison 210-2 X 3,152,938 10/1964 Davis et al.210-11 FOREIGN PATENTS 953,414 3/1964 Great Britain 195-116 OTHERREFERENCES Combating Pollution Created by Oil Spills, Vol. I Methods,Arthur D. Little, Inc., AD 696-635, June 30, 1969, U.S. Dept.Commerce/National Bureau of Standards, pp. 87-94, 104-406.

THOMAS G. WYSE, Primary Examiner U.S. Cl. XLR.

2l0-DIG. 21; 195-3 H

1. THE METHOD OF REMOVING OILS AND HYDROCARBONS FROM THE SURFACE OF ABODY OF WATER COMPRISING DISPERSING A FREEZE-DRIED HYDROCARBON CONSUMINGMICROOGANISM COMPOSITION COMPRISING MICROORGANISMS ADSORBED WITHIN ANINORGANIC MICROPOROUS CARRIER ONTO SAID OILS AND HYDROCARBONS, SAIDSURFACE HAVING WATER AND MOISTURE PRESENT WHEREBY SAID MICROORGANISMCOMPOSITION IS ACTIVATES, ADN ALLOWING SAID MICROORGANISM COMPOSITION TOREMAIN IN CONTACT WITH SAID OILS AND HYDROCARBONS WHEREBY THEMICROORGANISMS IN SAID COMPOSITION DIGEST AND REMOVE THE OILS ANDHYDROCARBONS.